package com.atguigu.gulimall.search.service.impl;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.TypeReference;
import com.atguigu.common.to.es.SkuEsModel;
import com.atguigu.common.utils.R;
import com.atguigu.gulimall.search.config.GulimallElasticSearchConfig;
import com.atguigu.gulimall.search.constant.EsConstant;
import com.atguigu.gulimall.search.feign.ProductFeignService;
import com.atguigu.gulimall.search.service.MallSearchService;
import com.atguigu.gulimall.search.vo.AttrResponseVO;
import com.atguigu.gulimall.search.vo.BrandVO;
import com.atguigu.gulimall.search.vo.SearchParam;
import com.atguigu.gulimall.search.vo.SearchResult;
import com.google.common.collect.Lists;
import org.apache.lucene.search.join.ScoreMode;
import org.elasticsearch.action.search.SearchRequest;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.client.RestHighLevelClient;
import org.elasticsearch.index.query.BoolQueryBuilder;
import org.elasticsearch.index.query.NestedQueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.index.query.RangeQueryBuilder;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;
import org.elasticsearch.search.aggregations.AggregationBuilders;
import org.elasticsearch.search.aggregations.bucket.nested.NestedAggregationBuilder;
import org.elasticsearch.search.aggregations.bucket.nested.ParsedNested;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedLongTerms;
import org.elasticsearch.search.aggregations.bucket.terms.ParsedStringTerms;
import org.elasticsearch.search.aggregations.bucket.terms.Terms;
import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
import org.elasticsearch.search.builder.SearchSourceBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightBuilder;
import org.elasticsearch.search.fetch.subphase.highlight.HighlightField;
import org.elasticsearch.search.sort.SortOrder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.StringUtils;

import javax.annotation.Resource;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.List;
import java.util.stream.Collectors;

/**
 * @author : PF_23
 * @Description : 搜索服务实现类
 * @date : 2021/9/12 11:13.
 */
@Service
public class MallSearchServiceImpl implements MallSearchService {

    @Resource
    private RestHighLevelClient client;

    @Autowired
    private ProductFeignService productFeignService;

    /**
     * 去es检索
     *
     * @param param 检索的所有参数
     * @return 返回的检索结果, 里面包含所有的查询信息
     */
    @Override
    public SearchResult search(SearchParam param) {
        // 动态构建出查询需要的dsl语句
        // 1、准备检索请求
        SearchRequest searchRequest = buildSearchRequest(param);

        SearchResult result = null;
        try {
            // 2、执行检索请求
            SearchResponse response = client.search(searchRequest, GulimallElasticSearchConfig.COMMON_OPTIONS);
            // 3、分析相应数据封装成我们需要的格式
            result = buildSearchResult(response, param);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return result;
    }

    /**
     * 准备检索请求
     * # 模糊匹配，过滤（按照属性、分类、品牌、价格区间、库存）、排序、分页、高亮。聚合分析
     *
     * @return
     */
    private SearchRequest buildSearchRequest(SearchParam param) {
        // 构建dsl语句
        SearchSourceBuilder sourceBuilder = new SearchSourceBuilder();
        /**
         * 查询：模糊匹配，过滤（按照属性、分类、品牌、价格区间、库存）
         */
        // 1 构建bool -query
        BoolQueryBuilder queryBuilder = QueryBuilders.boolQuery();
        // 1.1 must-模糊匹配
        if (!StringUtils.isEmpty(param.getKeyword())) {
            queryBuilder.must(QueryBuilders.matchQuery("skuTitle", param.getKeyword()));
        }
        // 1.2 bool -filter过滤:按照三级分类id查询
        if (param.getCatalog3Id() != null) {
            queryBuilder.filter(QueryBuilders.termQuery("catalogId", param.getCatalog3Id()));
        }
        // 1.3 bool -filter过滤:按照品牌id查询
        if (param.getBrandId() != null && param.getBrandId().size() > 0) {
            queryBuilder.filter(QueryBuilders.termsQuery("brandId", param.getBrandId()));
        }

        // 1.4 bool -filter过滤:按照属性查询
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            // attrs=1_5存:8寸&attrs=2_16G:32G
            for (String attr : param.getAttrs()) {
                BoolQueryBuilder boolQuery = QueryBuilders.boolQuery();
                // att ：1_5存:8寸
                String[] s = attr.split("_");
                // 检索属性id
                String attrId = s[0];
                // 这个id检索的属性值
                String[] attrValues = s[1].split(":");

                boolQuery.must(QueryBuilders.termQuery("attrs.attrId", attrId));
                boolQuery.must(QueryBuilders.termsQuery("attrs.attrValue", attrValues));
                // 每一个都必须得生成一个nested查询
                NestedQueryBuilder nestedQueryBuilder = QueryBuilders.nestedQuery("attrs", boolQuery, ScoreMode.None);
                queryBuilder.filter(nestedQueryBuilder);
            }
        }

        //  1.5 bool -filter 按照是否有库存进行查询 1：有； 0：无
        if (param.getHasStock() != null) {
            queryBuilder.filter(QueryBuilders.termQuery("hasStock", param.getHasStock() == 0));
        }

        //  1.6 bool -filter 按照价格区间进行查询
        if (!StringUtils.isEmpty(param.getSkuPrice())) {
            // 1_500/_500/500_
            /**
             * "range": {
             *             "skuPrice": {
             *               "gte": 0,
             *               "lte": 4000
             *             }
             *           }
             */
            RangeQueryBuilder rangeQuery = QueryBuilders.rangeQuery("skuPrice");
            String[] s = param.getSkuPrice().split("_");
            if (s.length == 2) {
                // 区间
                rangeQuery.gte(s[0]).lte(s[1]);
            } else if (s.length == 1) {
                if (param.getSkuPrice().startsWith("_")) {
                    rangeQuery.lte(s[0]);
                } else {
                    rangeQuery.gt(s[1]);
                }
            }
            queryBuilder.filter(rangeQuery);
        }

        // 把以前的所有条件都拿来进行封装
        sourceBuilder.query(queryBuilder);

        /**
         * 排序、分页、高亮
         */
        //2.1 排序
        if (!StringUtils.isEmpty(param.getSort())) {
            String sort = param.getSort();
            String[] s = sort.split("_");
            SortOrder order = s[1].equalsIgnoreCase("asc") ? SortOrder.ASC : SortOrder.DESC;
            sourceBuilder.sort(s[0], order);
        }

        //2.2 分页
        //pageNum:1 from:0 size:5 [0,1,2,3,4]
        //pageNum:2 from:5 size:5
        // from = (pageNum - 1) * size
        sourceBuilder.from((param.getPageNum() - 1) * EsConstant.PRODUCT_PAGE_SIZE);
        sourceBuilder.size(EsConstant.PRODUCT_PAGE_SIZE);

        //2.3 高亮
        if (!StringUtils.isEmpty(param.getKeyword())) {
            HighlightBuilder builder = new HighlightBuilder();
            builder.field("skuTitle");
            builder.preTags("<b style='color:red'>");
            builder.postTags("</b>");
            sourceBuilder.highlighter(builder);
        }

        /**
         * 聚合分析
         */
        // 1、品牌聚合
        TermsAggregationBuilder brand_agg = AggregationBuilders.terms("brand_agg").field("brandId").size(50);

        // 品牌聚合的子聚合
        brand_agg.subAggregation(AggregationBuilders.terms("brand_name_agg").field("brandName").size(1));
        brand_agg.subAggregation(AggregationBuilders.terms("brand_img_agg").field("brandImg").size(1));
        // 1、TODO(单纯为了颜色好区分) : 聚合品牌brand
        sourceBuilder.aggregation(brand_agg);

        // 2、分类聚合 catalog_agg
        TermsAggregationBuilder catalog_agg = AggregationBuilders.terms("catalog_agg").field("catalogId").size(50);
        // 分类聚合的子聚合
        catalog_agg.subAggregation(AggregationBuilders.terms("catalog_name_agg").field("catalogName").size(1));
        // 2、TODO(单纯为了颜色好区分) : 聚合分类catalog
        sourceBuilder.aggregation(catalog_agg);

        // 3、属性聚合 attr_agg
        NestedAggregationBuilder attr_agg = AggregationBuilders.nested("attr_agg", "attrs");
        TermsAggregationBuilder attr_id_agg = AggregationBuilders.terms("attr_id_agg").field("attrs.attrId");
        // 聚合分析出n当前attr_id对应的名字
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_name_agg").field("attrs.attrName").size(1));
        // 聚合分析出n当前attr_id对应的所有的可能属性值attrValue
        attr_id_agg.subAggregation(AggregationBuilders.terms("attr_value_agg").field("attrs.attrValue").size(50));
        attr_agg.subAggregation(attr_id_agg);
        // 3、TODO(单纯为了颜色好区分) : 聚合属性 attr
        sourceBuilder.aggregation(attr_agg);

        // 构建的DLS
        System.out.println("构建的DLS:" + sourceBuilder.toString());

        SearchRequest searchRequest = new SearchRequest(new String[]{EsConstant.PRODUCT_INDEX}, sourceBuilder);
        return searchRequest;
    }

    /**
     * 封装（构建）响应（结果）数据
     *
     * @param response
     * @return
     */
    private SearchResult buildSearchResult(SearchResponse response, SearchParam param) {

        SearchHits hits = response.getHits();
        List<SkuEsModel> skuEsModels = Lists.newArrayList();
        if (hits.getHits() != null && hits.getHits().length > 0) {
            for (SearchHit hit : hits.getHits()) {
                String source = hit.getSourceAsString();
                SkuEsModel esModel = JSON.parseObject(source, SkuEsModel.class);

                // 带关键字搜索时高亮显示
                if (!StringUtils.isEmpty(param.getKeyword())) {
                    HighlightField skuTitle = hit.getHighlightFields().get("skuTitle");
                    String string = skuTitle.getFragments()[0].string();
                    esModel.setSkuTitle(string);
                }
                skuEsModels.add(esModel);
            }
        }

        SearchResult result = new SearchResult();
        //1、返回的所有查询到的商品
        result.setProducts(skuEsModels);

        //2、当前所有商品涉及到的所有属性信息
        List<SearchResult.AttrVO> attrVOList = Lists.newArrayList();
        ParsedNested attr_agg = response.getAggregations().get("attr_agg");
        ParsedLongTerms attr_id_agg = attr_agg.getAggregations().get("attr_id_agg");
        for (Terms.Bucket bucket : attr_id_agg.getBuckets()) {
            SearchResult.AttrVO attrVO = new SearchResult.AttrVO();
            //得到属性的id
            long attrId = bucket.getKeyAsNumber().longValue();

            //得到属性名
            String attr_name = ((ParsedStringTerms) bucket.getAggregations().get("attr_name_agg")).getBuckets().get(0).getKeyAsString();
            //得到属性的所有值
            List<String> attrValues = ((ParsedStringTerms) bucket.getAggregations().get("attr_value_agg")).getBuckets().stream().map(item -> {
                String keyAsString = item.getKeyAsString();
                return keyAsString;
            }).collect(Collectors.toList());

            attrVO.setAttrId(attrId);
            attrVO.setAttrName(attr_name);
            attrVO.setAttrValue(attrValues);

            attrVOList.add(attrVO);
        }

        result.setAttrs(attrVOList);

        //3、当前所有商品涉及到的所有品牌信息
        List<SearchResult.BrandVO> brandVOList = Lists.newArrayList();
        ParsedLongTerms brand_agg = response.getAggregations().get("brand_agg");
        for (Terms.Bucket bucket : brand_agg.getBuckets()) {
            SearchResult.BrandVO brandVO = new SearchResult.BrandVO();
            //    得到品牌的id
            long brandId = bucket.getKeyAsNumber().longValue();
            //    得到品牌名
            String brandName = ((ParsedStringTerms) bucket.getAggregations().get("brand_name_agg")).getBuckets().get(0).getKeyAsString();
            //    得到品牌的图片
            String brandImg = ((ParsedStringTerms) bucket.getAggregations().get("brand_img_agg")).getBuckets().get(0).getKeyAsString();

            brandVO.setBrandId(brandId);
            brandVO.setBrandName(brandName);
            brandVO.setBrandImg(brandImg);
            brandVOList.add(brandVO);

        }
        result.setBrands(brandVOList);
        //4、当前所有商品涉及到的所有分类信息
        ParsedLongTerms catalog_agg = response.getAggregations().get("catalog_agg");
        List<SearchResult.CatalogVO> catalogVOS = Lists.newArrayList();
        List<? extends Terms.Bucket> buckets = catalog_agg.getBuckets();
        for (Terms.Bucket bucket : buckets) {
            SearchResult.CatalogVO catalogVO = new SearchResult.CatalogVO();
            // 得到分类id
            String key = bucket.getKeyAsString();
            catalogVO.setCatalogId(Long.parseLong(key));
            // 得到分类名
            ParsedStringTerms catalog_name_agg = bucket.getAggregations().get("catalog_name_agg");
            String string = catalog_name_agg.getBuckets().get(0).getKeyAsString();
            catalogVO.setCatalogName(string);

            catalogVOS.add(catalogVO);
        }
        result.setCatalogs(catalogVOS);
        //=============以上信息从聚合中获取=================

        //5、分页信息-页码
        result.setPageNum(param.getPageNum());
        //6、分页信息-总记录数
        long total = hits.getTotalHits().value;
        result.setTotal(total);
        //7、分页信息-总页码-计算得到
        int totalPages = (int) Math.ceil(total * 1.0 / EsConstant.PRODUCT_PAGE_SIZE);
        result.setTotalPages(totalPages);

        List<Integer> pageNavs = Lists.newArrayList();
        for (int i = 1; i <= totalPages; i++) {
            pageNavs.add(i);
        }
        result.setPageNavs(pageNavs);

        // 构建面包屑导航功能
        if (param.getAttrs() != null && param.getAttrs().size() > 0) {
            List<SearchResult.NavVO> navVOList = param.getAttrs().stream().map(attr -> {
                // 1、 分析每一个attrs传过来的参数值
                SearchResult.NavVO navVO = new SearchResult.NavVO();

                // attrs=2_5寸:6寸
                String[] s = attr.split("_");
                navVO.setNavValue(s[1]);
                R r = productFeignService.attrInfo(Long.valueOf(s[0]));
                result.getAttrIds().add(Long.valueOf(s[0]));
                if (r.getCode() == 0) {
                    AttrResponseVO data = r.getData("attr", new TypeReference<AttrResponseVO>() {
                    });
                    navVO.setNavName(data.getAttrName());
                } else {
                    navVO.setNavName(s[0]);
                }

                // 2、取消面包屑后，需要跳转到哪个地方.将请求地址里面的当前条件置空
                // 拿到当前的所有查询条件
                String replace = replaceQueryString(param, attr, "attrs");
                navVO.setLink("http://search.gulimall.com/list.html?" + replace);

                return navVO;

            }).collect(Collectors.toList());

            // 品牌，分类
            if (param.getBrandId() != null && param.getBrandId().size() > 0) {
                List<SearchResult.NavVO> navs = result.getNavs();
                SearchResult.NavVO navVO = new SearchResult.NavVO();

                navVO.setNavName("品牌");

                // 远程调用查询所有品牌
                R r = productFeignService.brandInfo(param.getBrandId());
                if (r.getCode() == 0) {
                    List<BrandVO> brandVOS = r.getData("brand", new TypeReference<List<BrandVO>>() {
                    });
                    StringBuffer stringBuffer = new StringBuffer();
                    String replace = "";
                    for (BrandVO brandVO : brandVOS) {
                        stringBuffer.append(brandVO.getBrandName()).append(";");
                        replace = replaceQueryString(param, brandVO.getBrandId() + "", "brandId");
                    }
                    navVO.setNavValue(stringBuffer.toString());
                    navVO.setLink("http://search.gulimall.com/list.html?" + replace);
                }

                navs.add(navVO);
            }

            result.setNavs(navVOList);


            // todo 分类：不需要导航取消
        }

        return result;
    }

    private String replaceQueryString(SearchParam param, String attr, String key) {
        String encode = null;
        try {
            encode = URLEncoder.encode(attr, "UTF-8");
            // 浏览器对空格的编码和java不一样
            encode.replace("+", "%20");
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        }
        String replace = param.get_queryString().replaceAll("&" + key + "=" + encode, "");
        return replace;
    }
}

